Rotatable arrangement, especially for dredges



o. H. HABERMAAS ETAL 3,020,107

ROTATABLE ARRANGEMENT, ESPECIALLY FOR DREDGES I 2 Sheets-Sheet 1 Feb. 6,1962 Filed Jan. 28, 1960 Fig.7

Feb. 6, 1962 o. H. HABERMAAS ETAL 3,020,107

ROTATABLE ARRANGEMENT, ESPECIALLY F OR DREDGES 2. Sheets-Sheet 2 FiledJan. 28, 1960 3329,10? Patented Feb. 6, 1962 3,020,107 ROTATAELEARRANGEMENT, ESPECIALLY FOR DREDGES Qtto Heinrich Hahermaas,Rheinhausen, and Qtto Hoppmann, Mulheirn-Heissen, Germany, assignors toBeteiligungsund Patentverwaltuugsgesellschaft mit beschranitterHat-tang, Essen, Germany Fiied Jan. 28, 196$, Ser. No. 5,274 Ciaimspriority, application Germany Feb. 4, 1959 @Claims. (Cl, sea -2st) Thepresent invention relates to a rotatable system, especially for dredges,having an upper structure rotatably journalled on a lower structureabout a vertical axis, said lower and upper structures being axiallyaligned by roller means which are preferably combined to groups andjournalled on one of said two structures while moving along an annularpath on the other structure.

Structures of the above mentioned type, particularly when employed inconnection with dredges have the drawback that undue feeding forces andother outer forces such as heavy wind may impair the proper guiding ofthe upper structure relative to the lower structure. Furthermore, withthe heretofore known structures of the type involved, considerableprecision work is required with regard to the creation of the circulartrack in which one structure is guided by the other structure in orderto assure a proper guiding of the structures relative to each other.

It is an object of the present invention to provide a rotatablestructure of the general type set forth above, which will overcome theabove mentioned drawbacks.

It is another object of this invention to provide a rotatable system ofthe general type set forth above, in which also when great horizontalforces act upon the upper structure, a proper guiding of the upperstructure relative to the lower structure will be assured regardless ofpossible deviations in the annular path, in which the upper structure isguided, from the true circular shape.

These and other objects and advantages of the invention will appear moreclearly from the following specification in connection with theaccompanying drawings, in which:

FIG. 1 illustrates partly a side view and partly a section of a lowerand upper structure of a dredge with the journalling of a roller group.

FIG. 2 represents a section along the line lIII of FIG. 1.

FIG. 3 is a section along the line III-III of FIG. I but on a smallerscale than that of FIG. 1.

FIG. 4 represents a portion of a section similar to that of FIG. 3 butpertaining to a slightly modified structure.

FIG. 5 illustrates partly in side view and partly in section a lowerstructure and an upperstru'cture with a modified journalling of a rollergroup, said section being taken along the line V-V of FIG. 6.

FIG. 6 is a section along the line VIVI of FIG. 5 but on a reduced scalewith regard to that of FIG. 5.

General arrangement The objects of the present invention are realizedprimarily in that at least one of the rollers or roller groups, on theupper or lower structure are journalled in such a Way that they aremovable in radial direction with regard to the vertical axis of rotationof the rotatable system, said roller or roller groups being continuouslyyieldably urged against an annular path on one of said structure.

The means for yieldably urging the roller or roller groups against saidyieldable path may consist for instance of a spring system orofhydraulic cylinder piston means mounted for instance at one end of alever, the other end of which carries the roller or roller group. Ifdesired, two or more fluid operable cylinder piston means may beassociated with each roller or each roller group and may be heldcontinuously under a certain pressure by a pump common thereto. If therollers carrying the upper structure are equipped with a hydraulic loadequalizer, those hydraulic cylinder piston means which press theradially movably journalled rollers against the annular path are actedupon by the same pressure source which conveys the hydraulic loadequalization.

For the sake of completeness, it may be mentioned that in connectionwith bucket wheel dredges having an upper structure guided relative to alower structure in horizontal direction by rollers, it is known tosupport that roller group which is arranged in the longitudinal centralplane of the upper structure by interposing a power measuring elementwhich when a certain pressure is ex ceeded causes a switch to turn offthe driving means for the dredge. This device, however, represents amere safety device to prevent the dredge from being endangered by toohigh a feeding force. This device, however, does not deal with theproblem underlying the present invention, namely to assure a preciseguiding of the upper structure relative to the lower structure also whenthe annular path deviates from a true circular shape. The fact that thesaid mentioned heretofore known arrangement with the safety device doesnot deal with the just mentioned problem according to the invention isalso evident from the fact that with the said heretofore knownstructure, the power measuring device maintains the upper end of a levercarrying the guiding roller group at normal feeding power of the bucketwheel in engagement with a non-yieldable abutment. Consequently, if withsuch a structure the annular path deviates from a true circular shape,the said roller group cannot engage those portions of the annular pathwhich have a radius exceeding that of the normal radius.

Structural arrangement Referring now to the drawings in detail,;thearrangement shown therein comprises an annular path or track I mountedon the upper side of the lower dredge structure 2 and also comprisessupporting rollers 3 for the upper dredge structure 4. The supportingrollers 3 are arranged in pairs respectively supported by rockers 5which latter by means of hydraulic cylinder piston systems 6 support theupper structure 4. The supporting rollers 3 form three groups. Thehydraulic cylinder piston systems 6 of each group are respectivelysupplied with oil under pressure by pumps 7 through conduits 8 so that aload equalization will be obtained between the rollers-of each of thethree groups.

The supporting rollers have no guiding rims or treads. Instead, theupper structure 4- is with regard .to lateral I forces. guided by fourgroups of rollers 9 which by means 3 of vertical rotatable shafts moveon a cylindrical annular track 10 connected to the lower dredgestructure 4. The guiding rollers 9 are arranged in pairs and supportedby rockers 11 each two of which are interconnected by a rocker beam 12adapted to pivot about a vertical shaft 13, 14.

The shafts 13 of two groups of guiding rollers 9 are fixedly connectedto the upper structure 4. In contrast thereto the shafts 14 of the twoother guiding roller groups form levers journalled in an extension orprotrusion 15 of the upper structure 4 by means of a horizontal shaft 16in such a way that the roller group is adapted to pivot or tilt in adirection radial to the vertical tilting axis 17 of the dredge upperstructure 4.

The upper end of each lever 14 has by means of pivots 18 journalledtherein the cylinder or a hydraulic cylinder piston system 19 the piston20 of which rests against the upper structure 4. The oil under pressureis supplied to the cylinders 19 of shaft 14 carrying the two movableroller groups through conduits 21 from a pump 22 common to saidcylinders 19.

By means of the hydraulic cylinder piston systems 19, 20, the radiallymovable roller groups are, through the intervention of levers 14 alwaysheld under the necessary pressure in engagement with the annular path ortrack 10. Therefore, if the track 10 should, due to lack of precisionwork not be precisely circular, it will nevertheless be assured that allguiding rolls 9 will always engage said track so that the upperstructure 4 with the lower structure 2 will always be in power lockedconnection, in other words, a closed power path will be secured.Consequently, the upper structure will be pre-' vented from lateraldisplacement relative to the lower structure by greater forces such asconsiderable wind or an inclination of the device.

The radially movable guiding rollers 9 may also by other yieldableforces be pressed against the track 10, as for instance by springs 25.As shown in FIGS. and 6, the corresponding forces may act upon theradially movable roller groups without the intervention of a shaft,lever or the like.

The tilting shafts 16 of the levers may be so arranged that a desiredtransmission ratio will be obtained. The number of the non-yieldablyjournalled guiding roller groups and of the yieldably journalled guidingroller groups may, depending on the respective prevalent conditions, bedifferent from that shown in FIGS. 1 to 4. For instance, twonon-yieldable and one yieldable roller group may be provided as shown inFIGS. 5 and 6.

The hydraulic cylinder piston systems 19, 20 which press the movableguiding rollers against the annular rail may instead by a separate pump22 be supplied with oil under pressure through conduits 23 by pumps 7pertaining to the hydraulic cylinder piston systems 6 of the respectivesupporting roller g oups (see FIG. 4). It is also possible in akinematically inverse arrangement to arrange the guiding rollers at thelower structure and to arrange the annular track pertaining thereto onthe upper structure.

It is, of course, to be understood that the present invention is, by nomeans, limited to the particular constructions shown in the drawings butalso comprises any modifications within the scope of the appendedclaims.

What we claim is:

l. A rotary arrangement, especially for rotatable dredges, whichcomprises: a lower structure, an upper structure, trackless supportingrollers interposed between said lower structure and said upper structureand supporting said upper structure for rotation about a vertical axis,centering rollers mounted on one of said structures and rotatable aboutvertical axes, circular guiding means mounted on the other one of saidstructures and engaged by said centering rollers, at least one of saidcentering rollers being movable radially with regard to the verticalaxis about which said upper structure is rotatable, and

means continuously yieldably urging said one centering rolleragainst'and holding the same in engagement with said circular guidingmeans, at least another one of said centering rollers beingnon-yieldably mounted.

2.. A rotary arrangement, especially for rotatable dredges, whichcomprises: a lower structure, an upper structure, trackless supportingrollers interposed between said lower structure and said upper structureand supporting said upper structure for rotation about a vertical axis,first lever means supported by one of said structures and respectivelytiltable about vertical axes, pairs of second lever mean pivotallyconnected to said first lever means for pivoting about vertical axes,the arrangement being such that each of said first lever means haspivotally connected thereto two of said second lever means inhorizontally spaced relationship to each other, centering rollersarranged in pairs, each of said second lever means carrying twohorizontally spaced centering rollers respectively rotatable aboutvertical axes, circular guiding means mounted on the other one of saidstructures and engaged by said centering rollers, at least one of saidsecond lever means with said centering rollers thereon being movableradially with regard to the vertical axis about which said upperstructure is rotatable, and means continuously yieldably urging thecentering rollers on said one second lever means against and holding thesame in engagement with said circular guiding means, at least anotherone of said second lever means with the centering rollers thereon beingnon-yieldably mounted.

3. A rotary arrangement especially for rotatable dredges, whichcomprises: a lower structure, an upper structure, trackless supportingrollers interposed between said lower structure and said upper structureand supporting said upper structure for rotation about a vertical axis,lever means tiltably journalled on one of said structures for rotationabout a horizontal axis, groups of centering rollers rotatable aboutvertical axes and supported by said one of said structures, at least oneof said groups of centering rollers being journalled on said levermeans, circular guiding means mounted on the other one of saidstructures and located in a plane perpendicular to said first mentionedvertical axis for engagement by said centering rollers, yieldable powermeans continuously urging said lever means in a radial direction withregard to said first mentioned vertical axis to hold said group ofcentering rollers supported by said lever means in engagement with saidcircular guiding means, at least another one of said groups of centeringrollers being non-yieldably mounted.

4. A rotary arrangement, especially for dredges, which comprises: alower structure, an upper structure, trackless supporting rollersinterposed between said lower structure and said upper structure andsupporting said upper structure for rotation about a vertical axis, aplurality of lever means tiltably journalled on one of said structuresfor tilting about a horizontal axis, at least two groups of centeringrollers respectively journalled on said lever means, circular guidingmeans mounted on the other one of said structures in a planeperpendicular to said vertical axis, a plurality of fluid operablecylinder piston means for urging the groups of rollers respectivelyconnected thereto in radial direction with regard to said vertical axisfor engagement with said circular guiding means, pump means common tosaid cylinder piston means for maintaining a certain pressure in saidcylinder piston means, at least a further centering roller non-yieldablymounted on said one structure.

5. A rotary arrangement, especially for dredges, which comprises: alower structure, an upper structure, trackless supporting rollersinterposed between said lower structure and said upper structure, firstcylinder piston means interposed between and connected to saidsupporting rollers and said upper structure for supporting the latter,said upper structure being adapted by means of said supporting rollersto rotate about a vertical axis,

centering rollers mounted on one of said structures and rotatable aboutvertical axes, circular guiding means mounted on the other one of saidstructures and engaged by said centering rollers, lever means on one ofsaid structures and tiltable about a horizontal axis, at least some ofsaid centering rollers being mounted on said lever means, secondcylinder piston means operatively connected to said lever means andcontinuously urging the centering rollers mounted thereon in a directionperpendicular to said vertical axis about which said upper structure isrotatable to hold the rollers supported by 6 said lever means inengagement with said circular guiding means, pump means common to atleast one cylinder of said first and of said second cylinder pistonmeans for maintaining a predetermined pressure therein.

References Cited in the file of this patent UNITED STATES PATENTS2,674,445 Diehl Apr. 6, 1954 2,718,168 Kendall et al Sept. 20, 19552,794,692 Nemeth June 4, 1957

